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metabolism

...glucosidase. After the two chains are separated, reaction [16] can occur again. The glucose 1-phosphate thus formed from glycogen or, in plants, from starch, is converted to glucose 6-phosphate by
phosphoglucomutase [78], which catalyzes a reaction very similar to that effected in step [8] of glycolysis; glucose 6-phosphate can then undergo further catabolism via glycolysis...

...polysaccharides—
i.e., glycogen in animals, starch in plants—reaction [77] is preceded by the conversion of glucose 6-phosphate to glucose 1-phosphate, in a reaction catalyzed by phosph oglucomutase [78]. Glucose 1-phosphate functions as R−Ⓟ in reaction [77a]. UTP is the specific NTP for glycogen synthesis in animals [77a];